🎨 Palette: Improve score readability and achievement feedback

[aidasofialily-cmd]

I have implemented a few micro-UX improvements to the "Speed Clicker" game:

1. Thousands-Separators: Large scores are now formatted with commas (e.g., 1,000,000 instead of 1000000) using a new formatWithCommas helper.
2. Visual Flair: The "NEW BEST!" message now includes sparkles (✨) and is styled with CLR_CTRL (Bold Yellow) for better celebratory impact.
3. HUD Consistency: Both the "Score:" and "High:" labels in the HUD are now styled with CLR_SCORE (Bold Cyan) for a more balanced look.
4. Contextual Feedback: The final congratulations message now explicitly mentions the previous personal best, helping players appreciate the scale of their improvement.
5. Terminal Hygiene: Added missing CLR_RESET sequences to ensure no color bleeds into the user's shell after gameplay.

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PR created automatically by Jules for task 821922923110433119 started by @aidasofialily-cmd

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